Method of Making Sandwich-Like Product Starting With Extruded Profile

ABSTRACT

A product ( 10 ) made from an extruded sheet or web of material ( 42 ) having a non-linear cross-section, and the process of making the product ( 10 ) is provided. The extruded web or extrudate ( 42 ) is plastically deformed in selected areas and then folded. When folded into the appropriate shape, the extrudate ( 42 ) is formed into a product ( 10 ) having a plurality of cells ( 14 ). The cells ( 14   a ) may have one or more openings ( 34   a ), allowing access to an interior of the cell ( 14   a ) and reducing the weight of the product ( 10   a ).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/345,166 filed Jan. 6, 2012 entitled “Method of Making Core forSandwich-Like Product Starting with Extruded Profile”, which is fullyincorporated by reference herein. U.S. patent application Ser. No.13/345,166 is a continuation-in-part of U.S. patent application Ser. No.11/566,973 filed Dec. 5, 2006 entitled “Folded Product Made FromExtruded Profile and Method of Making Same”, which is fully incorporatedby reference herein.

FIELD OF THE INVENTION

This invention relates generally to a sandwich-like product forstructural, packaging and other applications and the process of makingthe product.

BACKGROUND OF THE INVENTION

In the aerospace industry, honeycomb products have been used as a corecomponent for sandwich panels and boards that are resistant to bucklingand bending. These honeycomb products each comprise a plurality ofcells, which in cross-section have a generally hexagonal shape. Suchproducts may be fabricated from aluminum, fiber paper or plastic, amongother materials. A sandwich structure may be prepared having two coverlayers or skins which are welded, adhesively bonded or otherwise securedto the honeycomb product to create a multi-layered or multi-laminatematerial. Interest expressed in other industrial sectors concerning theuse of lightweight sandwich structures is continually growing, due atleast in part to the realization of its high strength properties whilemaintaining a relatively low structural weight-per-volume of product.

A multi-layered or multi-laminate material having a honeycomb product asthe core thereof may be used in the packaging industry. However, inautomobile part packaging and comparable markets, such a product mustcompete with corrugated paperboard or corrugated plastic or likematerials which may be produced quickly and relatively inexpensively.

U.S. Pat. No. 6,183,836 discloses a honeycomb core for use in a sandwichmaterial in which the material of the honeycomb core is cut and thenfolded to create a plurality of hexagonal cells. Due to the cuts in thesheet prior to folding the sheet, the resultant cells may be weaker thandesired.

A process for producing a folded honeycomb core for use in sandwichmaterials from a continuous uncut web is disclosed in U.S. Pat. No.6,726,974. U.S. Pat. No. 6,800,351 discloses another process forproducing a folded honeycomb core which includes scoring a corrugatedmaterial before rotating interconnected corrugated strips. The honeycombcore resulting from using either of these methods may have materialwhich adds to the weight of the honeycomb core, but may notsignificantly improve the strength of the honeycomb core.

Accordingly, there is a need for a product which may be used alone or ina multi-layered material, and which has a favorable strength-to-weightratio.

There is further a need for a process for manufacturing a product, suchas a core for use alone or in a multi-layered material, which is lessexpensive and may be produced in higher quantities than heretofore knownprocesses.

SUMMARY OF THE INVENTION

These and other objectives of the invention have been attained in aprocess for producing a core for use alone or in a sandwich-likeproduct. The process includes extruding a web of material which has anon-planar profile, i.e., has a non-linear cross-section, plasticallydeforming or treating portions of such web, and then folding the treatedweb to produce the core. The extrudate has a generally corrugated shapewith continuous peaks and valleys joined by connecting portions, allextending in the direction of travel of the extrudate.

The process of preparing a web of material suitable for furtherfabrication into a product is rendered efficient in part by producing anextrudate having a non-linear cross-section. For purposes of thisdocument, linear shall be defined as a single straight continuous line,the shortest distance between two points. Each of the extrudates orextruded webs illustrated herein has a non-planar profile and has anon-linear cross-section. Shapes of other webs of material not shown areintended to be included in such a definition. The extrudate displays anon-linear, cross-sectional configuration upon exiting the extruderhead. This cross-section may assume any of a variety of shapes.

According to one aspect of this invention, a process of making a productcomprises extruding a web of material having a predetermined or desiredwidth or transverse dimension, the extruded web having a generallynon-linear, cross-section; plastically deforming such as flatteningareas of the extruded web; and folding the web. As defined herein, theterm “web” encompasses material processed in extrusion equipmentintended to accept the specific material introduced into that equipment,and issuing or exiting from an extruder head.

During any of the processes described or shown herein, a plurality ofopenings may be introduced into the extruded web. These openings can beintroduced by stamping the material, but may also include processing ofthe extruded web by one or more tools to thereby form the openings. Asused herein, an opening is intended to encompass the situation in whichmaterial is removed from the web. The openings may be circular, but mayassume one of any number of other shapes, such as oval, hourglass,asymmetric, and the like. The process of plastically deforming orflattening selected areas of the extruded web may comprise contactingthe extruded web with an element which may be heated. Selected areas ofthe extruded web can be flattened by a tool at any desired temperatureapplying pressure, heat, or a combination of pressure and heat, in oneor more selected areas. The process of flattening may precede theintroduction of openings into the extruded web, may follow theintroduction of openings into the extruded web, or the two processes mayoccur substantially simultaneously.

One type of non-linear, cross-section shape which the extruded web maydisplay is a generally corrugated shape with peaks and valleys joined byconnecting portions, the peaks, valleys and connecting portions allextending in the direction of travel of the web during extrusion. Theextruded web is flattened in selected areas and then folded alongtransversely extending fold lines on the edges of the flattened areas.

According to another aspect of the invention, a process of making a corefor a sandwich-like product comprises extruding a web of material havinga generally non-planar profile comprising continuous corrugations withcontinuous peaks and valleys joined by connecting portions extending inthe direction of travel of the web. The next step in the processcomprises flattening selected areas of the extruded web using at leastone movable tool to interrupt the continuous corrugations to create aplurality of corrugated regions, each comprising a plurality ofcorrugations extending in a first direction generally parallel thedirection of travel of the extruded web and a plurality of flats, eachextending in a second direction perpendicular to the first direction.The next step in the process comprises folding the web along fold linesextending in the second direction. The extruded web is lastly cut at thedesired location to achieve the desired size of sandwich-like product.The outer skins may be applied to the core material at any desired timeof this process, including during the process or after the core has beencreated.

Regardless of the method used to create the core product, one advantageis that a lightweight, strong product may be quickly and easilymanufactured in a desired size or height. The product of this invention,which is produced according to the processes described herein, has agood strength-to-weight ratio even without forming openings in the web,and may be made from many different materials quickly and inexpensively.The strength-to-weight ratio may be improved by strategic removal ofmaterial from the extruded web at some time in the process. The productmay be used alone, incorporated into a multi-layered sandwich-likematerial, or used in any other desired manner.

BRIEF DESCRIPTION OF THE DRAWINGS

The objectives and features of the present invention will become morereadily apparent when the following detailed description of the drawingsis taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of a web of material having a generallynon-planar, cross-section being extruded from an extruder;

FIG. 1A is a perspective view of a web of material having a generallynon-linear, cross-section being extruded from an extruder head ofalternate design;

FIG. 1B is a perspective view of a web of material having a generallynon-linear, cross-section being extruded from an extruder head ofalternate design;

FIG. 1C is a perspective view of a web of material having a generallynon-linear cross-section being extruded from an extruder head ofalternate design;

FIG. 2 is a perspective view of a portion of the extruded web of FIG. 1;

FIG. 2A is a perspective view of a portion of the extruded web of FIG.1A;

FIG. 2B is a perspective view of a portion of the extruded web ofmaterial extruded from the extruder head of FIG. 1B;

FIG. 2C is a perspective view of a portion of the extruded web ofmaterial extruded from the extruder head of FIG. 10;

FIG. 3 is a perspective view of a portion of the extruded web of FIG. 2being treated to create transversely extending flats;

FIG. 3A is a side elevational view of a portion of the extruded web ofFIG. 1A being treated to create transversely extending flats;

FIG. 3B is an end view of the extruded web of FIG. 2B;

FIG. 3C is an end view of the extruded web of FIG. 2C;

FIG. 4 is a perspective view of a portion of the plastically deformedweb of FIG. 3 being folded to create rows of cells;

FIG. 4A is a side elevational view of the web of FIG. 3A being folded tocreate re-oriented portions containing channels;

FIG. 4B is a perspective view of a portion of the extruded web of FIG.2B being treated to create a plurality of plastically deformed areas orregions;

FIG. 5 is a perspective view of a portion of the plastically deformedweb of FIG. 3 being further folded to create a portion of a honeycombproduct;

FIG. 5A is a side elevational view of the web of FIG. 4A afterorientation to create a portion of a honeycomb product;

FIG. 5B is a perspective view of a portion of the plastically deformedweb of FIG. 4B being folded to create rows of cells;

FIG. 6 is a perspective view of a row of cells;

FIG. 6B is a perspective view of a portion of the extruded web of FIGS.1B-5B being folded to create a portion of a product;

FIG. 7 is a perspective view of a portion of the plastically deformedweb of FIG. 4 being treated to create a plurality of openings in theplastically deformed web;

FIG. 7B is a perspective view of a portion of the extruded web of FIG.2B being treated to create a plurality of plastically deformed areas orregions in the form of flats;

FIG. 8 is a perspective view of a portion of the plastically deformedweb of FIG. 7 being further folded to create rows of cells;

FIG. 8B is a perspective view of a portion of the plastically deformedweb of FIG. 7B being folded to create rows of cells;

FIG. 9 is a perspective view of an extruded web having been plasticallydeformed and punched simultaneously according to another aspect of thisinvention;

FIG. 10 is a perspective view of a portion of the plastically deformedweb of FIG. 9 being folded to create rows of cells;

FIG. 11 is a perspective view of a web of material having a generallynon-linear cross-section being extruded from an extruder head ofalternate design;

FIG. 11A is an enlarged view of the extruder head of FIG. 11;

FIG. 12 is a perspective view of a portion of an extruded web made withthe extruder head of FIG. 11;

FIG. 13 is a cross-sectional view taken along the line 13-13 of FIG. 12;

FIG. 13A is a cross-sectional view of an alternative extrusion;

FIG. 13B is a cross-sectional view of a core made from the extrusion ofFIG. 13A;

FIG. 13C is a cross-sectional view of an alternative extrusion;

FIG. 13D is a cross-sectional view of a core made from the extrusion ofFIG. 13C;

FIG. 13E is a cross-sectional view of an alternative extrusion;

FIG. 13F is a cross-sectional view of a core made from the extrusion ofFIG. 13E;

FIG. 13G is a cross-sectional view of an alternative extrusion;

FIG. 13H is a cross-sectional view of a core made from the extrusion ofFIG. 13G;

FIG. 14 is a perspective view of a portion of the extruded web of FIG.12 being treated to create transversely extending flats;

FIG. 15 is a perspective view of a portion of the treated web of FIG. 14being folded to create rows of cells;

FIG. 16 is a perspective view of a portion of the treated web of FIG. 14being further folded to create a portion of a core product;

FIG. 17 is a perspective view of a finished core product;

FIG. 18 is a cross-sectional view taken along the line 18-18 of FIG. 17;

FIG. 19 is an enlarged view of a portion of the treated and folded webof FIG. 16;

FIG. 20 is a perspective view of a portion of the treated web of FIG. 14being treated to create a plurality of openings in the web;

FIG. 21 is an enlarged view of another extruder head;

FIG. 22 is a perspective view of a portion of an extruded web made withthe extruder head of FIG. 21;

FIG. 23 is a cross-sectional view taken along the line 23-23 of FIG. 22;

FIG. 24 is a perspective view of a finished core product; and

FIG. 25 is a cross-sectional view taken along the line 25-25 of FIG. 24.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to FIG. 5, a portion of a honeycomb product 10, according toone embodiment of this invention, is shown. The honeycomb product 10 maybe made using numerous processes, including those described herein andothers within the scope of the claims. FIG. 5 shows a portion of ahoneycomb product 10 comprising a plurality of rows 12 of identicalcells 14 made from extruded web or sheet of material. FIG. 6 illustratesone such row 12 of cells 14. Referring to FIG. 5, the honeycomb product10 has a generally planar upper surface 16 in a generally horizontalplane P1 and a generally planar lower surface 18 in a generallyhorizontal plane P2, the distance between which defines the height H ofthe honeycomb product 10. The height H of the honeycomb product 10 maybe any desired distance and is not intended to be limited to the heightof the illustrated portion of the honeycomb product.

As shown in FIGS. 4 and 5, each row 12 of cells 14 is made by bringingtwo adjacent hinged row walls 20 together in an accordion-like manner.Each row wall 20 has alternating planar and non-planar regions or areas22, 24, respectively. Each non-planar region 24 in FIGS. 4 and 5comprises three rectangular walls comprising a half-hexagon incross-section. Regions 24 are bounded by planar regions 22. During theprocess of making the honeycomb product 10, adjacent row walls 20 arebrought together so that the planar regions 22 of adjacent row walls 20at least partially contact each other and the non-planar regions 24 ofrow walls 20 define sides or side walls 74, 76 of cells 14.

In certain applications, such as, for example, when a web ofthermoplastic material is heated at some stage in the manufacture of thehoneycomb product 10, the planar regions 22 of adjacent row walls 20 maybe bonded, welded or secured to each other without any additionalmaterial. Alternatively, adhesive or other bonding agent may be used tosecure adjacent row walls 20 together to complete the rows 12 of cells14. The non-planar regions 24 of adjacent row walls 20 are spaced apartand define the shape or configuration of the cells 14 after themanufacturing process has been completed. Outermost portions or sides 74of adjacent cells 14 in different rows 12 may contact each other and maybe secured to each other in certain applications of this invention.

Although the drawings illustrate each non-planar region 24 of each rowwall 20 having a cross-sectional configuration of a half-hexagon, thenon-planar regions of the row walls may have any desired cross-sectionalconfiguration, such as, for example, a curved or arcuate or sinuouscross-sectional configuration. The creation of the side walls or sides74, 76 of the cells 14 is described in more detail below. Depending uponthe application, the cells 14 may be any desired shape or size.

As best illustrated in FIG. 6, each cell 14 has a top 28 and a bottom 30of a predetermined size and/or shape. As shown in FIG. 5, the tops 28 ofthe cells 14 are located in plane P1 and make up part of the uppersurface 16 of the honeycomb product 10. Likewise, the bottoms 30 of thecells 14 are located in plane P2 and make up part of the lower surface18 of the honeycomb product 10. The top 28, bottom 30 and sides 72, 74of the cell 14 define a cell interior 32.

In the illustrated embodiment, each cell top 28 and bottom 30 is apolygon and, more particularly, a hexagon. However, if the non-planarregions of the row walls were in the shape of half a cylinder, then thetops and bottoms of the cells would be circular or oval and the cellswould have a cylindrical interior.

FIGS. 1-4 illustrate a method or process of making a honeycomb product10 which may be used alone, in a multi-layered material or product, orin any desired manner. FIG. 1 illustrates an extruder 40 extruding a webof material 42, which is shown in more detail in FIG. 2. Although oneconfiguration of extruder 40 and extruder head 41 is illustrated, anytype or configuration of extruder known in the art may be used. Theextruder and extruder head configurations will vary as a function of thematerial being extruded and the cross-section of the extrudate. Thematerial can include any of a variety of plastic compositions and anyother material capable of being extruded, and can encompass additionalcompositions which can be further processed to produce a honeycombproduct.

In FIG. 2, the extruded web 42 travels in a direction indicated by arrow43. The extrudate 42 has a pair of opposed side edges 45, the lineardistance between which defines the width or transverse dimension of theextruded web 42. The extruded web 42 may be any desired material of anydesired thickness and/or width.

The extruded web 42 has a generally non-linear, cross-section orcross-sectional configuration. In cross-section, the extruded web 42 hasa generally corrugated configuration or shape, including a plurality offlattened peaks 48 and a plurality of flattened valleys 50 joinedtogether by connecting portions 52. Each of the flattened peaks 48,flattened valleys 50 and connecting portions 52 are longitudinallyextending as shown in FIG. 2. The flattened valleys 50 are all generallyco-planar in a horizontal plane P3. Likewise, the flattened peaks 48 areall generally co-planar in a horizontal plane P4 above the plane P3. Thelinear distance between the planes P3 and P4 defines the height H1 ofthe corrugations 46. Although one shape or configuration of extruded web42 is illustrated in FIG. 2, the extruded web 42 may assume numerousother non-linear configurations in cross-section. For example, theexpanded view of the extruder head in FIG. 1A shows an alternatecross-sectional shape which can be used to create the non-linear,cross-section extruded web. A perspective view of the extruded web 42′formed by the alternate extruder head design is provided in FIG. 2A.

FIGS. 3 and 4 illustrate a step in this process of making honeycombproduct 10 comprising plastically deforming or flattening at leastselected portions or areas 54, 56 of the extruded web 42 to create aplastically deformed extruded web 58. This plastic deformation mayinclude using movable tools 60, 61, such as shown in FIG. 3 to interruptthe continuous corrugations 46 formed in the emerging extruded web 42and create a plurality of corrugated regions or areas 62, eachcomprising a plurality of corrugations 46 extending in a first directiongenerally parallel the direction of travel 43 of the extruded web 42 orlongitudinally, and a plurality of flats or flattened areas 54, 56 eachextending in a second direction perpendicular to the first direction,transversely or from side-to-side. The size of these regions or areas62, 54 and 56 may vary depending upon the desired size or shape of thecells 14 of the honeycomb product 10.

Although tool 60 is illustrated as comprising three bars 64 joinedtogether with connectors 66 (only one being shown for clarity), and tool61 is illustrated as comprising two bars 64 joined together withconnectors 65 (only one being shown for clarity), respectively, thesetools 60, 61 may comprise any number of bars of any desired size orconfiguration joined together or not. Although two tools areillustrated, any number of tools of any desired type or configurationmay be used. Again, the term tool is not intended to be limiting and mayinclude any tool known in the art.

During the step of plastically deforming at least selected portions ofthe extruded web 42, the bars 64 of the tools 60, 61 may be chilled, atambient temperature, or heated by any desired method to facilitateprocessing. Such heating is illustrated schematically by arrows 38. Thisheating step is optional and may be used in certain applications only.In other applications, it may be omitted partially or entirely. Althoughit is shown schematically after the flats 54, 56 have been created inthe extruded web 42, this heating step may occur any time during thismanufacturing process.

Due to the creation of the flattened areas or flats 54, 56, eachcorrugation 46 may have an end portion 69 which extends between a peak48 and a valley 50. These end portions 69 are illustrated as each beingin the shape of a trapezoid, but may be other shapes, depending upon theshape of the corrugations.

As best illustrated in FIGS. 3 and 4, each generally rectangular,transversely extending flat or flattened area 56 is located in the planeP3 of the extruded web 42. Each generally rectangular, transverselyextending flat or flattened area 54 is located in plane P4 above theplane P3 of the extruded web 42 and co-planar with the plane of theflattened peaks 48 of corrugations 46. Flattened areas 56 and 54alternate between corrugated regions 62. As seen in FIG. 4, due to theshape of the tools 60, 61, each flat or flattened area 54 has side walls70 extending from the outer edges of the flat 54 to the flattenedvalleys 50 in the corrugated regions 62. These side walls 70 areillustrated as each being in the shape of a trapezoid, but may be othershapes, depending upon the shape of the corrugations. Although notshown, the corrugations may have a semi-circular, sinuous, curved orother cross sectional configuration.

As shown in FIG. 4, the plastically deformed web portion 58 is thenfolded along transversely extending fold lines 72 located generally onthe edges of the flats 54, 56. Such fold lines 72 may be optionallyscored or perforated at any step in the manufacturing process with cuts71 to assist folding. Such scoring may be made by a separate tool ortools. As shown in FIG. 5, after the plastically deformed web portion 58is folded along transversely extending fold lines 72, side walls 70 layunderneath and may contact the raised flat 54, and end walls 69 ofcorrugations 46 rest on and contact flats 56.

As best illustrated in FIG. 6, side walls 70 abut and are underneathportions of the raised flats 54. These two-ply areas compriseapproximately half of the tops 28 of some of the cells 14. In suchcells, the bottom 30 of the cell 14 is a single-ply which was formed inthe flat 56 before folding. As shown in FIG. 6, end walls 69 abut andare above portions of the flats 56 to form approximately half of thebottoms 30 of other cells 14. In such cells, the top 28 of the cell 14is a single-ply which was formed in the flat 54 prior to folding. Thus,in one row 12 of cells 14, each cell 14 has a single-ply top 28 and adouble-ply bottom 30. In adjacent rows of cells 14, each cell 14 has adouble-ply top 28 and a single-ply bottom 30.

As shown in FIGS. 4, 5 and 6, after the plastically deformed web portion58 is folded along transversely extending fold lines 72, thecorrugations 46 or non-planar regions 24 of the row walls 20 become theside walls 74,76 of the cells 14. More particularly, the generallyplanar peaks 48 of corrugations 46 shown in FIG. 4 become the outmostside walls 74 of the cells 14, and the generally planar connectingportions 52 of corrugations 46 become additional side walls 76 of thecells 14. As shown in FIGS. 5 and 6, within a row 12 of cells 14, theplanar portions 22 of row walls 20 come together to create flattenedtwo-ply portions 77 of row 12. Side walls 74, 76, along with the top 28and bottom 30 of each cell 14, define a cell interior 32.

The last step in the process is to cut the extruded web 42 at anydesired location. FIG. 4 illustrates a cutter 78 at one location.However, one or more cutting tools or devices may be used at any desiredlocation to create a honeycomb product 10 of a desired length.

FIGS. 7-8 illustrate another method or process of making a honeycombproduct which may be used alone or in a multi-layered material orproduct. FIG. 7 illustrates an extruded web 42 a traveling in adirection indicated by arrow 43 a and having a pair of opposed sideedges 45 a, the linear distance between which defines the width ortransverse dimension of the extruded web 42 a. The extruded web 42 a maybe any desired material of any desired thickness and/or width. Theextruded web 42 a is identical to extruded web 42 described above.

The extruded web 42 a is then treated as described above and illustratedin FIG. 3 to create a plastically deformed web portion 58 a having aplurality of corrugations 46 a. As seen in FIG. 7, the corrugations 46 amay comprise co-planar flattened peaks 54 a in a plane P6 and flattenedvalleys 56 a in the plane P5 of the extruded web 42 a with generallyrectangular flat connecting portions 52 a extending therebetween.Lastly, each corrugation 46 a may have an end portion 69 a. These endportions 69 a are illustrated as each being in the shape of a trapezoid,but may be other shapes, depending upon the shape of the corrugations.

As best illustrated in FIG. 7, each generally rectangular, transverselyextending flat or flattened area 56 a is located in the plane P5 of theextruded web 42 a. Therefore, each generally rectangular, transverselyextending flat or flattened area 54 a is located in plane P6 above theplane P5 of the extruded web 42 a and co-planar with the flattened peaks48 of corrugations 46 a. Flattened areas 56 a and 54 a alternate betweencorrugated areas 62 a. Each flat 54 a has side walls 70 a extending fromthe outer edges of the flat 54 a to the flattened valleys 50 a in thecorrugated regions 62 a. These side walls 70 a are illustrated as eachbeing in the shape of a trapezoid, but may be other shapes, dependingupon the shape of the corrugations. Although not shown, the corrugationsmay have a semi-circular, sinuous, curved or other cross sectionalconfiguration.

FIG. 7 illustrates a movable tool 82 in the form of a punch press whichis used to remove material 84 from plastically deformed web 58 a inpredetermined or preselected locations. In FIG. 7, the punch press ortool 82 has a plurality of punchers 86 mounted on a plate 88 atpreselected or predetermined locations or positions to create aplurality of rectangular openings 34 a through predetermined orpreselected portions of the plastically deformed web 58 a. Theseopenings 34 a become the openings in the honeycomb product 10 adescribed above. See FIG. 8. Although illustrated as being rectangular,the openings 34 a may be of any predefined desired size or shape andstrategically located at any desired location on a portion of unrolledweb. For example, the holes or openings 34 a may be circular and beoriented such that each cell 14 has at least one opening 34 a allowingaccess to the interior of the cell 14.

Although a punch press is illustrated, any other tool, such as a lasercutter, may be used to create the openings 34 a through any portion ofthe plastically deformed portion 58 a of the extruded web 42 a tolighten the extruded web 42 a so that when this portion of the web 42 ais formed into a honeycomb product 10 a, the resultant honeycomb product10 a has a relatively high strength-to-weight ratio due, at least inpart, to the removal of such material during the process ofmanufacturing the honeycomb product.

Although the tool 82 is illustrated beneath the extruded web 42 a, tool82 may be located above the extruded web 42 a or at any desiredlocation. More than one tool may be used if desired.

As shown in FIGS. 7-8, the strategic locations of the openings 34 a aresuch that the openings 34 a are located along the flats 54 a, 56 a ofthe plastically deformed web 58 a, along the flattened peaks 48 a of thecorrugations 46 a and along connecting portions 52 a of corrugations 46a. As shown in FIG. 7, each opening 34 a is illustrated as beinggenerally rectangular, but may be any predefined or preselected shape orsize. As shown in FIGS. 7 and 8, some of the holes 34 a in flats 54 a,56 a extend through the bottoms 30 a and tops 28 a of cells 14 a.Likewise, holes 34 a through the connecting portions 52 a of thecorrugations 62 a extend through the side walls 76 a of cells 14 a.

As shown in FIG. 7, after the openings 34 a have been bored, punched orotherwise made, the plastically deformed web portion 58 a is then foldedalong transversely extending fold lines 72 a located generally on theedges of the flats 54 a, 56 a. As shown in FIGS. 7 and 8, after theplastically deformed web 58 a is folded along transversely extendingfold lines 72 a, side walls 70 a lay underneath the raised flats 54 aand end walls 69 a of corrugations 62 a rest on flats 56 a.

The last step in the process is to cut the extruded web 42 a at anydesired location. FIG. 7 illustrates a cutter 78 a at one location.However, one or more cutting tools or devices may be used at any desiredlocation to create a honeycomb product 10 a of a desired length.

FIG. 8 shows a portion of the resultant honeycomb product 10 a alongwith skins or layers 80 (shown in phantom), one or both of which may besecured to at least one of the upper and lower surfaces 16 a, 18 a ofhoneycomb product 10 a to create a multi-layered product for any desireduse. Such skins may be incorporated into a product having a honeycombcore or product made in accordance with any aspect of the presentinvention, including via any method described or contemplated herein.

FIGS. 9-10 illustrate another method or process of making a honeycombproduct 10 b which may be used alone or in a multi-layered material orproduct.

FIGS. 9 and 10 illustrate another method or process of making ahoneycomb product 10 b which may be used alone or in a multi-layeredmaterial or product, comprising plastically deforming at least portionsof the extruded web 42 b. Plastic deformation may include using movabletools 60 b, 61 b, such as shown in FIG. 9 to create a plurality ofcorrugated regions or areas 62 b comprising a plurality of corrugations46 b extending in a first direction generally parallel the direction oftravel 43 b of the web 42 b or longitudinally, and a plurality offlattened areas or regions 54 b, 56 b, each extending in a seconddirection perpendicular to the first direction, transversely or fromside-to-side. The size of these regions or areas 62 b, 54 b and 56 b mayvary depending upon the desired size or shape of the cells 14 b of thehoneycomb product 10 b. See FIG. 10.

FIG. 9 illustrates movable tools 60 b, 61 b, which, in addition toplastically deforming the extruded web 42 b, also remove material 84 bfrom plastically deformed web 58 b in predetermined or preselectedlocations. In FIG. 9, each of the tools 60 b, 61 b has a plurality ofpunchers 86 b mounted on bars 64 b at preselected or predeterminedlocations or positions to create a plurality of circular openings 34 bthrough predetermined or preselected portions of the plasticallydeformed web 58 b. These openings 34 b become the openings in thehoneycomb product 10 b described above. Although illustrated ascircular, the openings 34 b may be of any desired shape andstrategically located at any desired location on a portion of theextruded web.

Although one configuration of tool 60 b (and 61 b) is illustratedcomprising bars 64 b joined by connectors 66 b (and 65 b), any otherconfiguration or type of tool may be used to plastically deform extrudedportions of web 42 b. Such tools may simultaneously create openings 34 bthrough any portion of the extruded web to lighten the extruded web 42 bso that when this portion of the web 42 b is folded to create honeycombproduct 10 b, the resultant honeycomb product 10 b has a relatively highstrength-to-weight ratio due, at least in part, to the removal of suchmaterial during the process of manufacturing the honeycomb product 10 b.

Although the tools 60 b and 61 b are illustrated respectively above andbelow extruded web 42 b, the orientation of tools 60 b and 61 b may bereversed, or at any other desired location, such as one after the otherin a staggered format. Any number of tools 60 b, 61 b may be used ifdesired.

During the step of plastically deforming at least selected portions ofthe extruded web 42 b, the bars 64 b of the tools 60 b, 61 b may bechilled, at ambient temperature, or heated by any desired method tofacilitate processing. Such heating is illustrated schematically byarrows 38 b. This heating step is optional and may be used in certainapplications only. In other applications, it may be omitted partially orentirely. This heating step may occur any time during this manufacturingprocess.

As shown in FIG. 10, after the web 42 b has been plastically deformedand the openings 34 b have been created, the plastically deformed webportion 58 b is then folded along transversely extending fold lines 72 blocated generally on the edges of the flats 54 b, 56 b. As shown inFIGS. 9 and 10, after the plastically deformed web of material 58 b isfolded along transversely extending fold lines 72 b, side walls 70 b layunderneath the raised flats 54 b and end walls 62 b of corrugations 60 brest on flats 56 b.

The last step in the process is to cut the plastically deformed extrudedweb 58 b at any desired location. FIG. 10 illustrates a cutter 78 b atone location. However, one or more cutting tools or devices may be usedat any desired location to create a honeycomb product 10 b of a desiredlength.

As noted above, the cross-section of the extruded web can assume anynumber of shapes. FIGS. 1A-5A illustrates an alternative method ofproducing a honeycomb product and the product made by that method.

The temperature needed to process a plasticated material through anextruder and out an extruder head, such as 41′ in FIG. 1A, inconjunction with the properties of the material being extruded, theextruder speed, and complexity of the desired cross-section shape, maycreate an extruded web 42′ which may retain an unacceptably highinternal heat after exiting the extruder head 41′. If not cooled to anacceptable temperature promptly after exiting the extruder head, such anextrudate may warp or show other indicia of degradation due to excessivelevels of heat being retained. As shown in FIG. 2A, the channels 44 ofthe web 42′, though open at one end, may be otherwise effectively closedto transport air or other heat exchange medium. Such channels 44 aredescribed herein as being closed.

To improve access, one or more access openings 101 may be introducedinto one or more longitudinally extending channels 44 of the web 42′.Creation of an access opening 101 into a channel forms a modifiedchannel 44′, described herein as being substantially closed. See FIG.2A. The access opening 101 may be created in the web 42′ by appropriatemachining of the extruder head 41′, or by the action of a cutting ormaterial-removing tool (not shown) downstream of the extruder head 41′.Only one access opening 101 is shown in FIG. 2A on only one channel 44,but additional channels 44 can have one or more access openings 101, upto all of the channels in the extrudate. The access opening or openingscan vary in size or shape as needed to facilitate transport ofsufficient quantities of a heat exchange medium between the interior andexterior of a channel 44. The access opening 101 is depicted as beingcontinuous along the channel 44, but this is not required. Any number ofaccess openings 101 may be any desired length. FIG. 1A depicts analternate extrusion cross-section shape, as shown in extruder head 41′.FIG. 2A depicts an alternate extruded web 42′ formed by use of extruderhead 41′ containing closed corrugations, or channels 44, the channel asdepicted having a hexagonal shape in cross-section.

FIGS. 3A-5A depict side elevational views of the process of flatteningportions of an extruded web of the general configuration depicted inFIG. 2A having channels therein, followed by folding and re-orientingportions of the extruded web to create a honeycomb structure, portionsof the extruded web being re-oriented at 90° relative to their originalmachine direction orientation or position.

As shown in FIG. 3A, sections 110 of the extruded web 42′ may beflattened by tools 116, alternating the sections 110 being compressedinto upper flats 118 and lower flats 120. Tool 116 may apply pressureonly, heat only, or a combination of pressure and heat, to create flats118, 120.

Additional portions 124 a-d shown in FIG. 3A each contain at least onechannel disposed horizontally, which may be either closed orsubstantially closed. At least one portion is capable of beingmanipulated by a folding operation to mate with an adjacent portion,i.e., 124 a with 124 b, 124 b with 124 c, or 124 c with 124 d, as shownin FIGS. 4A and 5A, to form vertically oriented cells 14′.

FIG. 4A depicts portions 124 a-d in varying degrees of re-orientation,from an original machine direction having closed channels disposedhorizontally, to an orientation at 90° relative to the original machinedirection, wherein the channels, now cells 14′, are substantiallyvertical. The portions 124 a-d re-orient along hinge lines 128.

FIG. 5A depicts the portions 124 a-d, along with similarly disposedportions, after folding and re-orientation. The resulting honeycombproduct 10′ is comprised in part of re-oriented portions 124 a, 124 b,124 c, and 124 d, with upper flats 118 and lower flats 120,respectively, disposed above and below selected portions 124 a-124 d,the upper and lower flats being offset relative to each other.

FIG. 1B depicts an extruder 40″ with an alternate extruder head 41″ usedto extrude an extrusion 42″ having a non-planar profile and non-linearcross-section, as shown in FIGS. 2B and 3B. FIG. 2B depicts a portion ofthe extruded web 42″ formed by use of extruder head 41″, the extrudedweb 42″ having a non-linear, cross-section. For purposes of thisdocument, the portion of extruded web 42″ shown in FIG. 2B has anon-planar profile because it does not comprise a single solid flatsheet of material. The present invention is intended to cover allextrusions which are not solid flat sheets or webs of material.

As seen in FIG. 3B, the extruded web 42″ has spaced upper and lowerhorizontal walls 130 in planes P7 and P8, the linear distance betweenthese planes defining the height H2 of the extrudate 42″. The extrudate42″ also has side walls 132, the distance between which defines thewidth or transverse dimension W2 of the extrudate 42″. Lastly, theextrudate 42″ has a plurality of spacers 134 extending between thehorizontal walls 130 and spaced from each other so as to define aplurality of flutes or channels 136 which extend longitudinally or inthe direction of travel 43 of the web. As shown in FIG. 3B, these flutesor channels 136 have a rectangular shape in cross-section. As seen inFIG. 2B, the extruded web 42″ travels in a direction indicated by arrow43. The extruded web 42″ may be any desired material of any desiredthickness and/or width. This type of extrusion, if made of plastic, isknown as one type of corrugated plastic.

One advantage of the present invention is the ability to extrude aproduct with reduced weight or density compared to the weight or densityof a single solid sheet or web of the same material of the samedimensions. Due to the presence of holes, flutes or channels 136 in theextrudate 42″, as best shown in FIG. 3B, the weight of any length ofextrudate 42″ is less than half the weight of a solid piece of materialof the same dimensions. The same is also true of the extrudate shown inFIG. 2.

FIGS. 4B and 5B illustrate additional steps in this process of makingproduct 10″. FIG. 4B illustrates the step of plastically deforming atleast selected portions or areas 138 of the extruded web 42″ to create aplastically deformed extruded web 58″. This plastic deformation mayinclude using movable tools 140, 142, such as shown in FIG. 4B, tointerrupt the continuous corrugations or flutes 136 formed in theemerging extruded web 42″ and create a plurality of generally V-shapedplastically deformed regions or areas 138, each extending generallyperpendicular to the direction of travel 43 of the extruded web 42″ ortransversely or from side-to-side. The size of these regions or areas138 may vary depending upon numerous factors, including the desired sizeor shape of the cells 14 of the resulting product 10″.

Although tool 140 is illustrated as comprising six deforming members 144joined together with connectors 146 (only one being shown for clarity),and tool 142 is illustrated as comprising five deforming members 148joined together with connectors 150 (only one being shown for clarity),respectively, these tools 140, 142 may comprise any number of deformingmembers of any desired size or configuration, joined together or not.Although two movable tools are illustrated, any number of tools of anydesired type or configuration may be used. Again, the term tool is notintended to be limiting and may include any tool known in the art.

During the step of plastically deforming at least selected portions ofthe extruded web 42″, the deforming members 144, 148 of tools 140, 142,respectively, may be chilled, at ambient temperature, or heated by anydesired method to facilitate processing. Such heating is illustratedschematically by arrows 152. This heating step is optional and may beused in certain applications only. In other applications, it may beomitted partially or entirely. Although it is shown schematically duringthe creation of the plastic deformed areas 138 of the extruded web 42″using tools 140, 142, this heating step may occur any time during thismanufacturing process.

As shown in FIGS. 5B and 6B, the plastically deformed web portion 58″ isthen folded along transversely extending fold lines 154 locatedgenerally in the planes P7 and P8 of the extrudate 42″. See FIG. 3B.Such fold lines 154 may be optionally scored or perforated at any stepin the manufacturing process with cuts (not shown) to assist folding.Such scoring may be made by a separate tool or tools. As shown in FIG.6B, after the plastically deformed web portion 58″ is folded alongtransversely extending fold lines 154, horizontal walls 130 of extrudate42″ become vertically orientated, and the flutes 136 become thevertically oriented cells 14″ of the resultant product 10″.

Another step in the process may be to cut the extruded web 42″ at anydesired location. FIG. 4B illustrates a cutter 78 at one location.However, one or more cutting tools or devices may be used at any desiredlocation to create a product 10″ of a desired length.

FIG. 6B shows a portion of the resultant product 10″ along with skins orlayers 80 (shown in phantom), one or both of which may be secured to atleast one of the upper and lower surfaces of product 10″ to create amulti-layered or sandwich-like product for any desired use. As shown inFIG. 6B, the plastically deformed web 58″ is folded alternatively inupper and lower planes P7 and P8 to create a plurality of blocks 137,each block 137 containing a row 139 of vertically oriented cells 14″. Ifdesired, adjacent blocks 137 may be adhesively or otherwise joined toeach other to create product 10″, with or without any skins 80.

FIGS. 7B and 8B illustrate another method or process of making a product160, which may be used alone or in a multi-layered material or product.FIG. 7B illustrates an extruded web 42″ like the one described above andshown in FIGS. 1B, 2B and 3B, traveling in a direction indicated byarrow 43.

This method comprises plastically deforming or flattening at leastselected portions or areas 162, 164 of the extruded web 42″ to create aplastically deformed extruded web 166. This plastic deformation mayinclude using movable tools 168, 170, such as shown in FIG. 7B tointerrupt the continuous corrugations or flutes 136 formed in theemerging extruded web 42″ and create a plurality of non-deformed regionsor areas 172 and a plurality of flats or flattened areas 162, 164, eachextending in a second direction perpendicular to the direction of travelof the extruded web, transversely or from side-to-side. The size andlocation of these regions or areas 162, 164 and 172 may vary dependingupon the desired size or shape of the cells 165 of the resultant product160.

Although tool 168 is illustrated as comprising three bars 174 joinedtogether with connectors 176 (only one being shown for clarity), andtool 170 is illustrated as comprising two bars 174 joined together withconnectors 180 (only one being shown for clarity), respectively, thesetools 168, 170 may comprise any number of bars of any desired size orconfiguration joined together or not. Although two tools areillustrated, any number of tools of any desired type or configurationmay be used. Again, the term tool is not intended to be limiting and mayinclude any tool known in the art.

During the step of plastically deforming at least selected portions ofthe extruded web 42″, the bars 174 of the tools 168, 170 may be chilled,at ambient temperature, or heated by any desired method to facilitateprocessing. Such heating is illustrated schematically by arrows 178.This heating step is optional and may be used in certain applicationsonly. In other applications, it may be omitted partially or entirely.Although it is shown schematically after the flats 162, 164 have beencreated in the extruded web 42″, this heating step may occur any timeduring this manufacturing process.

As best illustrated in FIGS. 7B and 8B, each generally rectangular,transversely extending flat or flattened area 162 is located in theplane P8 of the extruded web 42″. Each generally rectangular,transversely extending flat or flattened area 164 is located in plane P7above the plane P8 of the extruded web 42″. Flattened areas 162 and 164alternate between corrugated or non-deformed regions 172. Eachcorrugated region 172 comprises rows of corrugations.

As shown in FIG. 5B, the plastically deformed web portion 166 is thenfolded along transversely extending fold lines 154 located generally inthe planes P7 and P8 of the extrudate 42″. See FIG. 3B. Such fold lines154 may be optionally scored or perforated at any step in themanufacturing process with cuts (not shown) to assist folding. Suchscoring may be made by a separate tool or tools. As shown in FIG. 6B,after the plastically deformed web portion 166 is folded alongtransversely extending fold lines 154, horizontal walls 130 of extrudate42″ become vertically orientated, and the flutes 136 become the cells14″ of the resultant product 160.

FIG. 8B shows a portion of the resultant product 160 along with skins orlayers 80 (shown in phantom), one or both of which may be secured to atleast one of the upper and lower surfaces of product 160 to create amulti-layered or sandwich-like product for any desired use. As shown inFIG. 8B, the plastically deformed web 166 is folded alternatively inupper and lower planes P7 and P8 to create a plurality of blocks 161,each block 161 containing a row of vertically oriented cells like theones shown in FIG. 6B. If desired, adjacent blocks 161 may be adhesivelyor otherwise joined to each other to create product 160 with or withoutskins 80.

Another step in the process may be to cut the extruded web 166 at anydesired location. FIG. 7B illustrates a cutter 78 at one location.However, one or more cutting tools or devices may be used at any desiredlocation to create a product 160 of a desired length.

FIG. 1C depicts an extruder 40 c with an alternate extruder head 41 cused to extrude an extrusion having a non-planar profile and non-linear,cross-section, as shown in FIGS. 2C and 3C. FIG. 2C depicts a portion ofthe extruded web 42 c formed by use of extruder head 41 c, the extrudedweb 42 c having a non-linear, cross-section. FIG. 2C depicts analternate extruded web 42 c formed by use of extruder head 41 c, theextruded web 42 c having a non-linear, cross-section. As seen in FIG.3C, the extruded web 42 c has spaced upper and lower horizontal walls182 in planes P9 and P10, the linear distance between these planesdefining the height H3 of the extrudate 42 c. The extrudate 42 c alsohas side edges 184, the distance between which defines the width ortransverse dimension W3 of the extrudate 42 c. Lastly, the extrudate 42c has a sinuous middle member 186 extending between the horizontal walls182 so as to define a plurality of flutes or channels 188 which extendlongitudinally. As seen in FIG. 2C, the extruded web 42 c travels in adirection indicated by arrow 43. The extruded web 42 c may be anydesired material of any desired thickness and/or width. Such an extrudedweb 42 c may be treated or processed as described above to create aproduct for use alone or in a sandwich-like core product.

FIGS. 11-19 illustrate a method or process of making a multi-layered orsandwich-like product 200, shown in FIGS. 17 and 18. The product 200comprises upper and lower generally planar skins 258 secured to a middlecore 198. FIG. 11 illustrates an extruder 202 having an extruder head204 shown in more detail in FIG. 11A.

As best shown in FIG. 11A, the extruder head 204 comprises a movablefirst or upper piece 206 having a jagged or tooth-shaped lower edge 208and a movable second or lower piece 210 having a jagged or tooth-shapedupper edge 212. Each piece 206, 210 may be independently movablerelative to the other, as shown by arrows 211. A gap 214 between thelower edge 208 of the upper piece 206 and the upper edge 212 of thelower piece 210 defines the size of the extrudate or web of material 216exiting the extruder head 204. In particular, the distance “D” betweenthe lower edge 208 of the upper piece 206 and the upper edge 212 of thelower piece 210 defines the thickness “T” of the extrudate 216 exitingthe extruder head 204. Although one configuration of extruder 202 isillustrated, any type or configuration of extruder known in the art maybe used. The extruder and extruder head configurations will vary as afunction of the material being extruded and the cross-section of theextrudate. The material can include any of a variety of plasticcompositions and any other material capable of being extruded, and canencompass additional compositions which can be further processed toproduce a sandwich-like product for packaging or other desiredapplications.

As shown in FIG. 12, the extruded web 216 travels in a directionindicated by arrow 218. The extruded web 216 has a pair of opposed sideedges 220, the linear distance between which defines the width ortransverse dimension of the extruded web 216. The extruded web 216 maybe any desired material of any desired shape, i.e., thickness and/orwidth.

The extruded web 216 has a generally non-planar profile or non-linear,cross-section or cross-sectional configuration. In cross-section, theextruded web 216 has a generally corrugated configuration or shape,including a plurality of peaks 222 and a plurality of valleys 224 joinedtogether by connecting portions 226, all extending in the direction oftravel of the web shown by arrows 218 during the extrusion process. Eachof the peaks 222, valleys 224 and connecting portions 226 arelongitudinally extending, as shown in FIG. 12, extending parallel theouter edges 220 of the extruded web 216. The valleys 224 are allgenerally co-planar in a horizontal plane P₁₁. Likewise, the peaks 222are all generally co-planar in a horizontal plane P₁₂ above the planeP₁₁. The linear distance between the planes P₁₁ and P₁₂ defines theheight “HH” of the corrugations 228. Although one shape or configurationof extruded web 216 is illustrated in FIGS. 12 and 13, the extruded web216 may assume numerous other non-linear configurations incross-section, such as those shown in FIGS. 13A, 13C, 13E and 13G.

FIGS. 14 and 15 illustrate part of the process of making the core 198 ofthe sandwich-like product 200 shown in FIG. 17. This part of the processcomprises plastically deforming or flattening at least selected portionsor areas 230, 232 of the extruded web 216 to create a plasticallydeformed or treated extruded web 234 shown being folded in FIG. 15. Thisplastic deformation may include using movable tools 236, 238, such asthose shown in FIG. 14, to interrupt the continuous corrugations 228formed in the extruded web 216 and create a plurality of corrugatedregions or areas 240 between adjacent flattened areas 230, 232. Eachcorrugated region 240 comprises a plurality of corrugations 228extending in a first direction generally parallel the direction oftravel 218 of the extruded web 162 or longitudinally, and a plurality offlats or flattened areas 230, 232 each extending in a second directionperpendicular to the first direction, transversely or from side-to-side.The size of these regions or areas 230, 232 and 240 may vary dependingupon the desired size or shape of the cells of the core 198.

Although upper tool 236 is illustrated as comprising three parallel bars242 joined together with connectors 244 (only one being shown forclarity), and lower tool 238 is illustrated as comprising two bars 243joined together with connectors 245 (only one being shown for clarity),respectively, these tools may comprise any number of bars of any desiredsize or configuration joined together with any number of connectors ornot. Although two tools are illustrated, any number of tools of anydesired type or configuration may be used. Again, the term tool is notintended to be limiting and may include any tool known in the art.

During the step of plastically deforming or flattening at least selectedportions 230, 232 of the extruded web 216, the bars 242, 243 of thetools 236, 238 may be chilled, at ambient temperature, or heated by anydesired method to facilitate processing. Such heating is illustratedschematically by arrows 38. This heating step is optional and may beused in desired applications only. In other applications, it may beomitted partially or entirely. Although it is shown schematically afterthe flats 230, 232 have been created in the extruded web 216, thisheating step may occur any time during this manufacturing process.

Due to the creation of the flattened areas or flats 230, 232, eachcorrugation 228 may have end portions 246, each end portion 246extending between a peak 222 and a valley 224. These end portions 246are illustrated as each being in the shape of a triangle, but may beother shapes, depending upon the shape of the corrugations.

As best illustrated in FIGS. 14 and 15, each generally rectangular,transversely extending flat or flattened area 232 is located in thelower plane P₁₁ of the extruded web 216. Each generally rectangular,transversely extending flat or flattened area 230 is located in upperplane P₁₂ above the lower plane P₁₁ of the extruded web 216 andco-planar with the plane of the peaks 222 of corrugations 228. Flattenedareas 232 and 230 alternate between corrugated regions 240. In otherwords, one flat 232 and one flat 230 are on opposite sides of acorrugated region 240.

As shown in FIG. 15, after the extruded web 216 is treated orplastically deformed to create treated extruded web 234, treatedextruded web 234 is then folded along transversely extending fold lines248 located generally on the edges of the flats 230, 232. Such foldlines 248 may be optionally scored or perforated at any step in themanufacturing process with cuts to assist folding. Such scoring may bemade by a separate tool or tools.

As shown in FIG. 16, after the plastically deformed web 234 is foldedalong transversely extending fold lines 248, end portions 246 lieunderneath and may contact the raised flat 230, and end portions 246 ofcorrugations 228 rest on and contact lower flats 232. In other words, asshown in FIG. 19, the triangular portions 250 of the upper horizontalportions 254 of core 198 are two plies thick, the lower ply being theend portions 246 of corrugations 228 before the treated web 234 isfolded along fold lines 248. The remainder of the upper flat 230comprises single-ply diamond-shaped areas 252. The same is true on thelower horizontal portions 256 of core 198.

As shown in FIG. 16, as the treated web 234 is folded along fold lines248, an upper skin 258 is secured to the upper horizontal portions 254of core 198, and a lower skin 258 is secured to the lower horizontalportions 256 of core 198. This step may occur separately orsimultaneously with the folding step described above. As shown in FIG.16, the upper horizontal portions 254 of core 198 are located generallyin a horizontal plane P₁₃, and the lower horizontal portions 256 of core198 are located generally in a horizontal plane P₁₄. The linear distancebetween horizontal planes P₁₃ and P₁₄ comprises the height “H₄” of thecore 198.

The last step in the process is to cut the treated web 234 at anydesired location. FIG. 16 illustrates a movable cutter 260 at onelocation. However, one or more cutting tools or devices may be used atany desired location to cut the treated web 234.

As shown in FIG. 18, after the treated web 234 is folded along foldlines 248, the connecting portions 226 of the corrugations 228 of thecorrugated regions 240 become side walls 262 of the cells 264 of thecore 198. Peaks 222 of the corrugations 228 of one of the corrugatedregions 240, shown in FIG. 15, contact peaks 222 of the corrugations 228of an adjacent corrugated region 240 after the treated web 234 isfolded. Similarly, valleys 224 of the corrugations 228 of one of thecorrugated regions 240, shown in FIG. 15, contact valleys 224 of thecorrugations 228 of an adjacent corrugated region 240 after the treatedweb 234 is folded.

As shown in FIG. 18, side walls 262, along with the flats 230, 232 oftreated web 234, define a cell 264 having a cell interior 266 after thetreated web 234 is folded and the skins 258 applied to the upper andlower horizontal portions 254, 256 of the folded web.

FIG. 20 illustrates a movable tool 268 in the form of a punch presswhich is used to remove material 270 from treated web 234 inpredetermined or preselected locations. In FIG. 20, the punch press ortool 268 has a plurality of punchers 272 mounted on a plate 274 atpreselected or predetermined locations or positions to create aplurality of openings 276 through predetermined or preselected portionsof the treated web 234. These openings 276 become the openings in acore, like the core 198 described above. Although illustrated as beingrectangular, the openings 276 may be of any predefined desired size orshape. For example, the openings may be circular or oval-shaped.Similarly, although illustrated as being formed only in the flats 230,232 of the treated web 234, the openings may be strategically located atany desired location or locations. For example, the openings may belocated, such that each cell 264 has at least one opening through thetop or bottom of the cell 264, allowing access to the interior 266 ofthe cell 264.

Although a punch press is illustrated, any other tool, such as a lasercutter, may be used to create openings through any portion of thetreated web 234 to lighten the treated web 234 so that when treated web234 is formed into a core 198, the resultant sandwich-like product 200has a relatively high strength-to-weight ratio due, at least in part, tothe removal of such material during the process of manufacturing thecore 198.

Although the tool 268 is illustrated beneath the treated web 234, tool268 may be located above the treated web 234, or at any desiredlocation. More than one tool may be used if desired. The presentinvention does not intend to limit the tool or tools used to removematerial in any of the embodiments described or shown herein.

As shown in FIG. 20, after the openings 276 have been bored, punched orotherwise made, the treated web 234 is then folded, as described above.Although not shown in FIG. 20, any of the extruded webs described orshown herein, including but not limited to extruded web 216, may betreated, such that openings are created therein using any method shownor described herein before being flattened or further treated or afterthe flats are formed therein.

FIGS. 21-25 illustrate a method or process of making anothersandwich-like product having a central core. However, the core of thisembodiment is posturized or has regions or areas having differentcharacteristics. The multi-layered or sandwich-like product 300 is shownin FIGS. 24 and 25. The product 300 comprises upper and lower generallyplanar skins 302 secured to a middle core 304. FIG. 21 illustrates anextruder head 278 which may be used in any convention extruder,including those shown and described herein.

As shown in FIG. 21, the extruder head 278 comprises a movable first orupper piece 280 having a jagged or tooth-shaped lower edge 282, and amovable second or lower piece 284 having a jagged or tooth-shaped upperedge 286. Each piece 280, 284 may be independently movable relative tothe other, as shown by arrows 288. A gap 290 between the lower edge 282of the upper piece 280 and the upper edge 286 of the lower piece 284defines the size of the extrudate or web of material 292 exiting the gap290 of extruder head 278. In particular, the distance between the loweredge 282 of the upper piece 280 and the upper edge 286 of the lowerpiece 284 defines the thickness of the extrudate 292 exiting theextruder head 278. In this embodiment, the thickness of the extrudate292 is not uniform across the width of the extrudate 292, as shown inFIGS. 22 and 23 due to the configurations of the pieces 280, 284 of theextruder head 278. As shown in FIGS. 22 and 23, the extrudate 292 may bedivided into three different regions, two outer regions 294 of a uniformthickness “T₁” and a middle region 296 of a uniform thickness “T₂”,greater than the thickness “T₁” of the outer regions 294. After beingflattened in certain areas and folded, the core 304 has the skins 302applied and cut to size as described herein to create the finishedsandwich-like product 300 shown in FIG. 24.

FIG. 25 illustrates a cross-section of the core 304 having a pluralityof cells 306, each cell 306 comprising side walls 308, a top 310 and abottom 312 defining a hollow interior 314. The interior 314 isdiamond-shaped in cross-section, as seen in FIG. 25.

FIGS. 13A and 13B illustrate an alternative extrusion 216 a. Thisextrusion 216 a, shown in cross-section in FIG. 13A, has a generallynon-planar profile or non-linear, cross-section. In cross-section, theextruded web 216 a has a generally corrugated configuration or shape,including a plurality of peaks 222 a and a plurality of valleys 224 ajoined together by connecting portions 226 a, all extending in thedirection of travel of the web during the extrusion process. Each of thepeaks 222 a, valleys 224 a and connecting portions 226 a arelongitudinally extending, extending parallel the outer edges 220 a ofthe extruded web 216 a. The valleys 224 a are all generally co-planar ina horizontal plane P₁₅. Likewise, the peaks 222 a are all generallyco-planar in a horizontal plane P₁₆ above the plane P₁₅. The lineardistance between the planes P₁₅ and P₁₆ defines the height “HH_(a)” ofthe corrugations 228 a. At the junction of intersecting connectingportions 226 a, i.e., at each peak 222 a and each valley 224 a,additional material at locations 314 is extruded. The additionalmaterial may cause the extrudate 216 a to be stronger than if theadditional material were omitted.

FIG. 13B illustrates in cross-section a core 198 a made from theextrudate 216 a, shown in FIG. 13A. As shown in FIG. 13B, after theextruded web 216 a is partially flattened and folded along fold lines,the connecting portions 226 a of the corrugations 228 a of thecorrugated regions become side walls 262 a of the cells 264 a of thecore 198 a. More particularly, the peaks 226 a of the corrugations 228 aof the corrugated regions shown in FIG. 13A contact valleys 224 a of thecorrugations 228 a of the corrugated regions after the treated web isfolded. As shown in FIG. 13B, side walls 262 a along with the flats oftreated web define a cell 264 a having a cell interior 266 a after thetreated web is folded and the skins applied to the upper and lowerhorizontal portions of the folded web.

FIGS. 13C and 13D illustrate an alternative extrusion 216 b. Thisextrusion 216 b, shown in cross-section in FIG. 13C, has a generallynon-planar profile or non-linear, cross-section. In cross-section, theextruded web 216 b has a generally corrugated configuration or shape,including a plurality of peaks 222 b and a plurality of valleys 224 bjoined together by connecting portions 226 b, all extending in thedirection of travel of the web during the extrusion process. Each of thepeaks 222 b, valleys 224 b and connecting portions 226 b arelongitudinally extending, extending parallel the outer edges 220 b ofthe extruded web 216 b. The valleys 224 b are all generally co-planar ina horizontal plane P₁₇. Likewise, the peaks 222 b are all generallyco-planar in a horizontal plane P₁₈ above the plane P₁₇. The lineardistance between the planes P₁₇ and P₁₈ defines the height “HH_(b)” ofthe corrugations 228 b. At each peak 222 b and each valley 224 b,additional material is extruded so that each peak 222 b is generallyrectangular in cross-section and has a flattened top 316. Similarly,each valley 224 b is generally rectangular in cross-section and has aflattened bottom 318. The additional material may cause the extrudate216 b to be stronger than if the additional material were omitted.

FIG. 13D illustrates in cross-section a core 198 b made from theextrudate 216 b shown in FIG. 13C. As shown in FIG. 13D, after theextruded web 216 b is partially flattened and folded along fold lines,the connecting portions 226 b of the corrugations 228 b of thecorrugated regions become side walls 262 b of the cells 264 b of thecore 198 b. More particularly, the top surfaces 316 of peaks 226 b ofthe corrugations 228 b of the corrugated regions shown in FIG. 13Dcontact the flattened bottom surfaces of valleys 224 b of thecorrugations 228 b of the corrugated regions after the treated web isfolded. As shown in FIG. 13D, side walls 262 b, along with the flats oftreated web, define a cell 264 b having a cell interior 266 b after thetreated web is folded and the skins applied to the upper and lowerhorizontal portions of the folded web.

FIGS. 13E and 13F illustrate an alternative extrusion 216 c. Thisextrusion 216 c, shown in cross-section in FIG. 13D, has a generallynon-planar profile or non-linear, cross-section. In cross-section, theextruded web 216 c has a generally corrugated configuration or shape,including a plurality of peaks 222 c and a plurality of valleys 224 cjoined together by connecting portions 226 c, all extending in thedirection of travel of the web during the extrusion process. Each of thepeaks 222 c, valleys 224 c and connecting portions 226 c arelongitudinally extending, extending parallel the outer edges 220 c ofthe extruded web 216 c. The valleys 224 c are all generally co-planar ina horizontal plane P₁₉. Likewise, the peaks 222 c are all generallyco-planar in a horizontal plane P₂₀ above the plane P₁₉. The lineardistance between the planes P₁₉ and P₂₀ defines the height “HH_(c)” ofthe corrugations 228 c. At each peak 222 c and each valley 224 c,additional material is extruded so that each peak 222 c is generallyrectangular in cross-section and has a flattened top 320. Similarly,each valley 224 c is generally triangular in cross-section and has aflattened bottom 322. The additional material may cause the extrudate216 c to be stronger than if the additional material were omitted.

FIG. 13F illustrates in cross-section a core 198 c made from theextrudate 216 c shown in FIG. 13E. As shown in FIG. 13F, after theextruded web 216 c is partially flattened and folded along fold lines,the connecting portions 226 c of the corrugations 228 c of thecorrugated regions become side walls 262 c of the cells 264 c of thecore 198 c. More particularly, the top surfaces 320 of peaks 226 c ofthe corrugations 228 c of the corrugated regions shown in FIG. 13Econtact the flattened bottom surfaces 322 of valleys 224 c of thecorrugations 228 c of the corrugated regions after the treated web isfolded. As shown in FIG. 13F, side walls 262 c, along with the flats oftreated web, define a cell 264 c having a cell interior 266 c after thetreated web is folded and the skins applied to the upper and lowerhorizontal portions of the folded web.

FIGS. 13G and 13H illustrate an alternative extrusion 216 d. Thisextrusion 216 d, shown in cross-section in FIG. 13G, has a generallynon-planar profile or non-linear cross-section. In cross-section, theextruded web 216 d has a generally corrugated configuration or shape,including a plurality of peaks 222 d and a plurality of valleys 224 djoined together by connecting portions 226 d, all extending in thedirection of travel of the web during the extrusion process. Each of thepeaks 222 d, valleys 224 d and connecting portions 226 d arelongitudinally extending, extending parallel the outer edges 220 d ofthe extruded web 216 d. The valleys 224 d are all generally co-planar ina horizontal plane P₂₁. Likewise, the peaks 222 d are all generallyco-planar in a horizontal plane P₂₂ above the plane P₂₁. The lineardistance between the planes P₂₁ and P₂₂ defines the height “HH_(d)” ofthe corrugations 228 d. At each peak 222 d and each valley 224 d,additional material is extruded so that each peak 222 d has a recess324. Similarly, each valley 224 d has a recess 326 which mates with orabuts the recess 324 of a peak 222 d when the extrudate is flattened andfolded. The additional material and configuration of the peaks andvalleys may cause the extrudate 216 d to be stronger than if theadditional material were omitted.

FIG. 13H illustrates in cross-section a core 198 d made from theextrudate 216 d shown in FIG. 13G. As shown in FIG. 13H, after theextruded web 216 d is partially flattened and folded along fold lines,the connecting portions 226 d of the corrugations 228 d of thecorrugated regions become side walls 262 d of the cells 264 d of thecore 198 d. More particularly, the inner surfaces 328 of peaks 226 d ofthe corrugations 228 c of the corrugated regions shown in FIG. 13Gcontact mating inner surfaces 330 of valleys 224 d of the corrugations228 d of the corrugated regions after the treated web is folded. Asshown in FIG. 13H, side walls 262 d, along with the flats of treatedweb, define a cell 264 d having a cell interior 266 d after the treatedweb is folded and the skins applied to the upper and lower horizontalportions of the folded web.

While I have described several preferred embodiments of the presentinvention, persons skilled in the art will appreciate changes andmodifications which may be made without departing from the spirit of theinvention. For example, although one configuration of a cell isillustrated and described, the cells of the present invention may beother configurations, such as cylindrical in shape. Therefore, I intendto be limited only by the scope of the following claims and equivalentsthereof.

I claim: 1-20. (canceled)
 21. A process of making a sandwich-likeproduct, said process comprising: extruding a web of material havingspaced parallel walls in first and second planes, respectively, and aplurality of spacers, each of the spacers extending between the wallsand being spaced from each other so as to define a plurality of flutes,each of the flutes having a rectangular shape in cross-section; cuttingportions of the extruded web using movable tools on opposite sides ofthe extruded web to create a plastically deformed web; folding theplastically deformed web along transversely extending fold lines locatedgenerally in the first and second planes to create a plurality ofblocks, each of the blocks containing a row of a cells to create amiddle core; applying generally planar outer skins to the tops andbottoms of the cells of the middle core to create a multi-layered web;and cutting the multi-layered web.
 22. The process of claim 21 whereinadjacent blocks are joined to each other.
 23. The process of claim 21wherein adjacent blocks are adhesively joined to each other.
 24. Theprocess of claim 21 wherein at least one of the movable tools is heated.25. The process of claim 21 wherein at least some of the fold lines arescored.
 26. The process of claim 1 wherein each of the tools hasmultiple cutting members.
 27. A process of making a sandwich-likeproduct, said process comprising: extruding a plastic web of materialhaving spaced walls in first and second planes, respectively, and aplurality of spacers, each of the spacers extending between the wallsand being spaced from each other so as to define a plurality of flutes,each of the flutes being rectangular in cross-section; interrupting theflutes of the extruded web using movable tools on opposite sides of theextruded web to create a plastically deformed web; folding theplastically deformed web along transversely extending fold lines locatedgenerally in the first and second planes such that the flutes of theextruded web become rows of cells in a middle core; applying generallyplanar outer skins to tops and bottoms of the blocks of the middle coreto create a multi-layered web; and cutting the multi-layered web. 28.The process of claim 27 further comprising forming a plurality ofopenings in the extruded web.
 29. The process of claim 27 whereinadjacent blocks are joined to each other.
 30. The process of claim 27wherein adjacent blocks are joined to each other with adhesive.
 31. Theprocess of claim 27 wherein at least one of the movable tools is heated.32. The process of claim 27 wherein at least some of the fold lines arescored.
 33. The process of claim 27 wherein each of the tools hasmultiple cutting members.
 34. A process of making a sandwich-likeproduct, said process comprising: extruding a web of material havingspaced walls in first and second planes, respectively, and a pluralityof spacers, each of the spacers extending between the walls and beingspaced from each other so as to define a plurality of continuous flutes,each of the continuous flutes having a rectangular shape incross-section; interrupting the continuous flutes of the extruded webusing movable tools on opposite sides of the extruded web to create aplastically deformed web; folding the plastically deformed web alongnon-perforated fold lines located alternatively in the first and secondplanes to create a plurality of blocks, each of the blocks containing arow of a cells to create a middle core; applying generally planar outerskins to the cells of the middle core to create a multi-layered web; andcutting the multi-layered web.
 35. The process of claim 34 furthercomprising forming a plurality of openings in the extruded web.
 36. Theprocess of claim 34 wherein adjacent blocks are joined to each other.37. The process of claim 34 wherein adjacent blocks are adhesivelyjoined to each other.
 38. The process of claim 34 wherein at least oneof the movable tools is heated.
 39. The process of claim 34 wherein allof the fold lines are scored.
 40. The process of claim 34 wherein eachof the tools has multiple deforming members.